1. Field of the Invention
The present invention relates generally to cursor control devices, and in particular, to an optical mouse having an integrated camera. The optical mouse with integrated camera can also be implemented with a notebook computer.
2. Background Art
To a personal computer (PC) user, the mouse is one of the basic devices utilized to input data into the PC, the other being the keyboard. Computer mice are often referred to as cursor positioning devices or cursor control devices, although mice are utilized to perform many other functions, such as to launch applications, re-size and move windows, drag, open and drop documents, select icons, text, menu items in a pull-down menu, and others. Unfortunately, the conventional computer mouse has several shortcomings.
First, prior art mice employ a rolling ball mechanism that is bulky. For example, for applications where space is a premium (e.g., lap-top computers), mice cannot be used effectively, and other cursor control devices, such as trackballs or touchpads, are preferred. Second, this ball mechanism wears out through use, and users often notice a degradation of mouse action and precision after extended use. In this regard, PC users have resigned themselves to the fact that when the ball mechanism is worn, they need to replace the worn mouse with a new mouse incurring undesirable hassle and costs. Third, even when the ball mechanism is not worn, the resolution and sensitivity of the conventional mouse is tolerable, but can be improved.
Recently, Logitech Corp. introduced a cursor control device marketed under the trademark xe2x80x9cMARBLExe2x80x9d. This device uses a trackball that is printed with a random pattern of dots. When the ball is moved, a light beam illuminates a small section of dots, and the image of this section is passed through a lens and reflected off a mirror. The reflected image is read by a sensor chip that calculates the movement of the dots. Unfortunately, this device requires a unique trackball having a special pattern of dots to feed the motion data to the sensor chip. Therefore, many of the above-mentioned drawbacks are still not resolved by this device.
In recent years, the advancement of complementary metal oxide semiconductor (CMOS) image sensor technologies has paved a way for the digital camera, video digital camera, and the PC camera to become the next low-cost peripheral device for the PC. For example, users can now use a PC camera and communication software (e.g., Microsoft""s free software, Net-Meeting) to send and receive live video images to and from a remote PC through a telephone line or local area network (LAN).
Unfortunately, despite these advances in image sensor technologies, an average PC user is not ready to accept the PC camera except for in limited uses, such as in security surveillance systems. An unresolved challenge to the PC industry is how to make the PC camera more useful and accepted by the average PC user.
Accordingly, there remains a need for an improved cursor control device that overcomes the disadvantages set forth previously.
It is an object of the present invention to provide a cursor control device that does not require a rolling ball mechanism, and that is compact, cost-effective to manufacture, and immune to the wear that a rolling ball mechanism is susceptible to.
It is another object of the present invention to provide an optical cursor control device that uses captured images to detect motion of the cursor control device, thereby improving the resolution and sensitivity of the cursor control device.
It is another object of the present invention to provide a cursor control device that can include an integrated camera.
In order to accomplish the objects of the present invention, an apparatus is provided that captures images that are used to manipulate a cursor. The apparatus includes an opto-electronic mechanism that is provided for receiving image signals. The received image signals are processed using digital signal processing (DSP) techniques and used to control movement of a cursor on a screen or display. In one embodiment, the DSP includes motion estimation.
The apparatus can be also be used for operation in two modes. In this embodiment, the apparatus also has a user-selectable trigger that allows a user to assert or de-assert a mode signal that determines whether operation is desired in a first mode or a second mode. The apparatus has a controller that is coupled to the opto-electronic mechanism and user-selectable trigger for receiving the mode signal. When operation is in the first mode, the received image signals are processed using DSP, and used to control movement of a cursor on a screen or display. When operation is in the second mode, the received image signals are processed and displayed as video images on a PC.
In one embodiment of the present invention, the apparatus can be a stand-alone device (such as a mouse) that is coupled to a personal computer. In another embodiment of the present invention, the apparatus can be integrated into the housing of a notebook computer for use therewith.
Thus, the apparatus of the present invention provides a single mechanism that has at least two different uses: to control cursor movement, and to capture video images. When used as a cursor control device, the apparatus of the present invention does not require a rolling ball mechanism, and is compact, cost-effective to manufacture, and immune to the wear that a rolling ball mechanism is susceptible to. In addition, the use of captured images and DSP to detect motion of the cursor control device improves the resolution and sensitivity of the cursor control device. When used as a camera, the apparatus of the present invention saves desktop space while providing a PC user with increased availability and visibility of digital image capture devices, as well as increased number of applications for and usefulness of the digital image capture devices.